Peritoneal
catheter-associated biofilm
infection is reported to be the main cause of refractory
peritonitis in
peritoneal dialysis patients. The application of antimicrobial lock
therapy, based on results on
central venous catheters, may be a promising option for treatment of biofilm-harboring peritoneal
catheters. This study investigated the effects of two lock solutions,
EDTA and
taurolidine, on an in vitro model of Pseudomonas aeruginosa biofilm-related peritoneal
catheter infection.
Silicone peritoneal
catheters were incubated for 24 h with a bioluminescent strain of P. aeruginosa. Then, serial dilutions of
taurolidine and/or
EDTA were applied (for 24 h) once or twice onto the contaminated
catheters, and P. aeruginosa viability/persistence were evaluated in real time up to 120 h using a Fluoroskan reader. On selected supernatants, high-performance liquid chromatography mass spectrometry (HPLC-MS) analysis was performed to measure the production of autoinducers (AI),
phenazines, and pyocyianines.
Taurolidine alone or in combination with
EDTA caused a significant decrease of bacterial load and biofilm persistence on the contaminated
catheters. The treatment did not lead to the sterilization of the devices, yet it resulted in a substantial destructuration of the
catheter-associated P. aeruginosa biofilm. HPLC-MS analysis showed that the treatment of biofilm-harboring
catheters with
taurolidine and
EDTA also affected the secretory activity of the pathogen.
EDTA and
taurolidine affect P. aeruginosa biofilm produced on peritoneal
catheters and profoundly compromise the microbial secretory profile. Future studies are needed to establish whether such lock solutions can be used to render peritoneal
catheter-related infections more susceptible to
antibiotic treatment. IMPORTANCE An in vitro model allows studies on the mechanisms by which the lock solutions exert their antimicrobial effects on
catheter-associated biofilm, thus providing a better understanding of the management of devise-associated
infections.